Earth moving machine incorporating power off-loading system



w. CARSTON Dec. 30, 1969 6 Sheets-Sheet 1 Original Filed March 1. 1966 3x 3 w l a Q m w M mm M WK I. 1 M Q3 i I :w m III M s 1 NM\ \A.\ W

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Dec. 30, 1969 w. CARSTON 3, 5

EARTH MOVING MACHINE INCORPORATING POWER OFF-LCADING SYSTEM Original Filed March 1, 1966 6 Sheets-Sheet 2 Ava 4 222 M1127? {Mex/v4 Dec. 30, 1969 w. CARSTON 3,486,251

EARTH MOVING MACHINE INCORPORATING POWER OFF-LOADING SYSTEM Original Filed March 1, 1966 6 Sheets-Sheet 5 W. CARSTON Dec. 30, 1969 EARTH MOVING MACHINE INCORPORATING POWER OFF-LOADING SYSTEM 6 Sheets-Sheet 4 Original Filed March 1, 1966 lllirLxlF Awnyrue (1/41 7!? (Ilia/V W. CAR STON Dec. 30, 1969 EARTH MOVING MACHINE INCORFORATING POWER OFF-LOADING SYSTEM 6 Sheets-Sheet 5 Original Filed March 1, 1966 rfrrmewzlr United States Patent O 3,486,251 EARTH MOVING MACHINE INCORPORATING POWER OFF-LOADING SYSTEM Walter Carston, 221 S. Front St., Delano, Calif. 93215 Original application Mar. 1, 1966, Ser. No. 538,424. Divided and this application Apr. 29, 1968, Ser. No. 725,047

Int. Cl. E02f 3/85, 3/62; 360p 1/00 US. Cl. 374- 8 Claims ABSTRACT OF THE DISCLOSURE A self-loading earth mover is disclosed including a rotary loading structure that is critically positioned in relation to a cutting blade at the forward termination of the load-carrying bowl. The loading structure includes two horizontal elongate blades fixed to revolve in a somewhat planetary manner whereby the blades are held against axial rotation as they are carried in a circular loading pattern of motion to cyclically receive earth from the cutting blade and carry such earth upward and rearward for distribution in the bowl. The loading blades are utilized to close the forward bowl opening while transporting the load. To discharge the load a power-driven discharge ram pushes the entire load forward, with a roller-borne false bottom carrying a large portion of the load to the forward opening without sliding friction. When the false bottom has travelled to the front of the bowl it is stopped, as the ram (having removed a substantial part of the load) can now provide sufficient force to overcome the sliding friction of the remaining load.

FIELD OF THE INVENTION This is a division of applicants United States patent application, Ser. No. 538,424, filed Mar. 1, 1966, now U. S. Patent No. 3,412,488, and directed to an earthmoving machine. More specifically, the subject matter hereof relates to off-loading structure in such a machine.

BACKGROUND AND SUMMARY OF THE INVENTION As a result of continued increases in population, advancements in technology and progress in general, it has become increasingly desirable to displace large volumes of earth so as to alter the natural terrain in many locations. For example, advancements in irrigation techniques as well as other agricultural developments have changed the requirements demanded of productive land. Therefore, in many geographical areas, terrain previously considered unproductive can now be efficiently farmed, particularly if graded to a desired plane. As a result, considerable need exists for an earth-moving machine of high capacity which can be economically manufactured and used to displace earth to accomplish a desired earth configuration from rough land, hills or other natural terrain. Of course, many other applications exist for such an earth-moving machine, including the construction of super highways, cutting canals, and excavation of building sites.

Over the years, the prior art has developed earth carriers which cut the terrain to a grade, excavating earth which is loaded and may then be transported to a desired location. The art involving these machines has continually sought to increase the size of the load which could be carried because the volumetric efficiency of these machines is quite siginficant. As a result, machines capable of loads in excess of 30 cubic yards have been proposed. However, such machines incorporating various techniques of the prior art have somewhat inherently been limited to approximately that capacity. This limitation occurs for several reasons. One of the problems in increasing the capacity of an excavating machine of the type under consideration resides in controlled unloading. That is, assuming a full bowl of very large capacity, it is readily apparent that such a bowl can be tipped, or otherwise dumped, to release the load in one location. However, it is also apparent that pushing the load out of the bowl at a controlled rate to spread it over an area, would require tremendous physical forces. For example, the controlled displacement of say fifty yards of earth so as to gradually move such a load from a bowl would normally require extreme forces. Therefore, a need exists for an excavating machine, basically including a bowl of large capacity, and incorporating an effective structure to unload the bowl at a controlled rate.

Generally, the present invention is directed to the combination of a form of offloading structure in an earthmoving machine. That is, the system comprises an improved earthmoving apparatus, which includes a bowl for receiving and carrying earth, which bowl is mounted on a mobile frame; the bowl having a somewhat open forward end, the lower edge of which includes a loading structure for effective loading; and further the apparatus includes an unloading structure for discharging earth from the bowl at a controlled rate by means of a movable floor or bottom structure.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a somewhat-distorted illustrative side elevation and diagrammatic view of a machine incorporating the principles of the present invention;

FIGURE 2 is a diagrammatic sectional view illustrating the operation of certain structure constructed in accordance with the present invention;

FIGURE 3 is a diagrammatic sectional view illustrating the operation of another structure in accordance with the present invention;

FIGURE 4 is a block diagrammatic representation of the power flow diagram of a system constructed in accordance with the present invention;

FIGURE 5 is a partial plan view of a structure incorporating the present invention;

FIGURE 6 is a fragmentary sectional view taken along line 66 of FIGURE 5;

FIGURE 6a is a sectional view taken along line 6a6a of FIGURE 6;

FIGURE 7 is a partial side elevation of the structure of FIGURE 5;

FIGURE 8 is a sectional view taken along line 8-8 of FIGURE 6;

FIGURE 9 is a sectional view taken along line 9-9 of FIGURE 6;

FIGURE 10 is a horizontally sectioned, enlarged plan view of the structure of FIGURE 5;

FIGURE 11 is a fragmentary, partially sectioned, front elevation view of the structure of FIGURE 5; and

FIGURE 12 is an enlarged vertically-sectioned view of a detailed portion of the structure of FIGURE 5.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENT Referring now initially to FIGURE 1, there is shown a machine system incorporating the present invention w which includes a tractor 2 coupled to a bowl-carrying structure 4. The tractor 2 (shown somewhat enlarged relative the bowl-carrying structure which is elsewhere shown in detail) is propelled by an engine 6 that drives wheels 8 as well known in the prior art which structural arrangement also affords guidance to the machine through a steering unit 9.

The bowl-carrying structure 4 is supported at its rear end on a pair of wheels and at its forward end by a gooseneck or other coupling 12 as well known, that is connected to the tractor 2 by a universal mount (not shown). The wheels 10, supporting the structure, are driven by an engine 14 carried at the rear of the bowlcarrying structure 4. Therefore, both the rear engine 14 and the forward engine 6 propel the system forward to drive a cutter 16 which excavates earth to load the bowl 15, as shown in accordance with a desired grading operation.

The rear engine 14 also drives a rotary loading structure 18 which moves and distributes earth from a location above and behind the cutter 16 into the bowl thereby enabling extremely large loads to be accumulated in the bowl. The engine 14 also drives a load pusher 17, which in cooperation with a particular floor or bottom structures enables controlled off-loading of the large volume of earth from the bowl 15.

In view of the above initial description of the general configuration of a machine or system constructed in accordance with the principles of the present invention, reference will now be made to the diagrammatic representation of FIGURE 2, illustrating the cooperative mech anisms for cutting and loading earth in accordance with the principles of the present invention.

In FIGURE 2 there is shown a section 20 of earth in which a cut to grade 22 is being accomplished. Accordingly, a cutting blade 24 is propelled forwardly as indicated so as to cut earth from the section 20 and then receive loose earth from that cut as an accumulation 26. Of course, as the cutting progresses, the size of the accumulation 26 is ever increasing and would eventually reach a magnitude suflicient to stop further cutting by the blade 24. However, as illustrated in FIGURE 2, the independent operation of the cutting blade 24 to cut and scoop earth from the section 20 in accordance with its forward motion is an important consideration relative to the present invention. That function is performed virtually entirely in accordance with the forward speed of the blade 24, which coincides to the forward speed of the machine. As a result, until the machine bowl is fully loaded, the operator may easily and conveniently control the forward speed of the system in accordance with the type of cut in progress, with little separate concern over the loading operation or the rate of cutting.

After the blade 24 has cut and received earth to provide the accumulation 26 as shown in FIGURE 2, a loading blade or scoop 28 engages the accumulation 26 of loose earth and moves it into the bowl of the apparatus (not shown in FIGURE 2). The scoop 28 may be provided in plurality and moves through a circular pattern in an upright position. That is, the blade is held against rotation while being carried through a circular pattern, and therefore remains substantially vertical (as shown) throughtout the entire circular path of travel, as indicated by the line 30. It is important to the operation of a system incorporating the principles of the present invention that the blade 28 acts only on loose earth in the accumulation 26, loading such earth into a bowl or other receiver of the apparatus. The distinctly different functions of cutting (by the blade 24) and loading by the independent structures (including the scoop 28) is extremely important in the present invention. This separation of sub-function results in a cooperation between the elements which permits effective earth cuts and simultaneously loads the loose earth from such cuts into a bowl that may be of substantially increased capacity. The effectiveness of the cooperating cutter and loading structure results in a need for an improved oif-loading structure which is incorporated in the disclosed embodiment of the present invention as described in detail below. Regarding the capacity of systems incorporating the principles of the present invention, no upper limits have been determined; however, it is noteworthy that an embodiment as disclosed herein, with a capacity of fifty-four cubic yards has been determined to be effective and convenient in use.

Referring now to the diagram of FIGURE 3, further preliminary consideration will now be directed to the structure for unloading a machine system of the present invention by discharging earth at a controlled rate so as to spread such earth over a large area. In FIGURE 3 there is shown a base supporting floor 32 comprising the actual bottom of a load-carrying bowl or bed incorporated in a system hereof. A portion of the floor 32 is covered by a superimposed bottom 34 which is movable in a plane parallel to the floor 32 as indicated by the arrow 36 as a result of bearing rollers 38 contained between the bottom 34 and the floor 32. When the bowl is full, as with an earth load 40, one portion of the load is disposed over the bottom 34 and the floor 32. Normally, the force that would be required to drive an off-loading plunger or ram 44 as to slide the entire earth load 40 off the floor 32 would be extremely great because of the mass of the load 40. However, in accordance with the principles hereof, the ram 44 engaging the earth load 40 can readily displace the .earth upon the application of a reasonable force, because of the peculiar supporting structure incorporating the rollers 38. That is, as the ram 44 is urged to the right (as shown) guided by side rollers 45 the section of the earth load 40 carried on the bottom 34 requires relatively little force for movement to the right with the result that the balance of the force is applied to shove the remaining earth to the right, off the floor 32. As the bottom 34 is moved to the right carrying a section of the earth load 40 along, a stop 47 is eventually reached, at which point, sufficient earth has been discharged so that the ram 44 may now slide the remaining earth off the bottom 34 and out of the bowl. Thus, the

ram continues to move, now over the bottom 34, and

slides the remaining earth 40 olf the now-displaced floor bottom 34. As a result, the bed or bowl may be unloaded at a controlled rate thereby discharging a significantlyincreased volume of earth from the high capacity bed or bowl. Thereafter, when the load has been completely discharged, the ram 44 may be withdrawn to the left by return power, or alternatively, it may be returned by accepting another load of earth, the accumulation of which returns the ram.

In view of the above preliminary descriptions relative certain structural aspects embodied in a system of the present invention, attention will now be directed to a detailed operating embodiment thereof as shown in FIG URES 4 through 12. In this regard, the power diagram of FIGURE 4 is representative of the energy distribution within the system, the control of which will now be considered. Of course, the particular power arrangement incorporated in the illustrative embodiment of the present invention and as diagrammatically represented in FIG- URE 4 represents merely one illustrative arrangement and it is to be understood that a wide variety of different power-distribution arrangements as well may be employed within the scope of the present invention as defined by the appended claims.

As indicated above, the system has a forward engine 6 and rear engine 14. The forward engine acts through a hydraulic control 48 which may comprise a torqueregulating transmission, to motivate a front-wheel drive 50 while the rear engine 14 acts through a hydraulic control 52 (which may take a similar form) to motivate a rear-wheel drive 54. Of course, a great many forms of variable-torque transmissions are readily available from a highly developed prior art, therefore, as related to the system of the present invention sufiice it to say that drive connection is provided from the rear engine 14 to the rear wheel drive 54 and from the forward engine 6 to the front wheel drive 50.

In the illustrative embodiment hereof, and as represented in the arrangement of FIGURE 4, the forward engine 6 also drives a hydraulic pump 56 thereby providing a source of hydraulic fluid (under pressure) which serves to control the position and operation of various components of the system. Specifically, the hydraulic pump may supply hydraulic fluid through valves 58 and 60 to control the operation of the wheel rear drive 54 and the front wheel 50 respectively. The fluid may also control clutches to in turn control the movement of the loading structure and the dumping or off-loading structure. Further in this regard, the pressurized fluid from the hydraulic pump 56 also sets the position of the cutting structure, positions the loading structure, return drives the off-loading structure, and adjusts the attitude of the bowl. Considering these functions somewhat individually, the hydraulic pump 56 controls a bowl actuator 62 (which may comprise a hydraulic activating cylinder) through a valve 64. That is, the valve 64 controls the application of fluid to the actuator 62 which is thus variously powered to raise or lower the forward end of the bowl and thereby change the attitude of the bowl relative the earths surface. In a somewhat similar fashion, a valve 66 controls the application of hydraulic fluid from the pump 56 to a cutter actuator 68 which varies the position of the cutter blade in accordance with the type of out being made and whether or not a cut is in progress. Still further, and in a similar manner, hydraulic fluid from the pump 56 is controlled by a valve 70 in application to a return actuator 72 which withdraws the ram 44. Still further, a valve 71 controls the applications of power fluid to a loader actuator 73 which positions the loading structure as desired in cooperation with the operation in progress.

These functions, considered above, relate to the movement of hydraulic actuators to accomplish a particular position or movement directly with the force of hydraulic fluid from the pump 56. In a somewhat-different manner the rear engine 14 provides motivating power for the loading apparatus 74 and the unloading apparatus 76. Specifically, the rear engine 14 provides rotary power through a hydraulic control 78, which may comprise a hydraulic clutch or amplifier, controlled by a valve to couple the rear engine 14 to the loading apparatus 74. In a somewhat similar manner, a hydraulic control 82, e.g. a clutch, controlled by a valve 84 controls the application of rotary power to the unloading apparatus 76 in accordance with control exercised through the valve 84. Of course, exemplary detailed structural forms, of the various apparatus as represented in FIGURE 4 will be considered below.

Reference will now be had to FIGURE 5 showing the rear portion of the physical system in plan view. The rear engine 14 is shown coupled through a torque converter 85 and a universal drive shaft 87 to a variabletorque automatic transmission 88. The rotary output of the transmission 88 is applied to a horizontal drive unit 91 and through a differential 89 to the rear Wheels 10.

The rotary energy applied to the drive unit 91 may be coupled to revolve the loader unit and drive the unloading ram as described below.

As the unit is propelled forward, by the combined drive applied to all four wheels, a cutter blade excavates an earth cut, producing loose earth that is to be loaded for transport. Such earth is received and distributed in a bowl 92 supported in a mobile frame and generally includes a bottom 93, side walls 95 and a back wall 97. The bowl 92 may of course be variously shaped to carry a substantial volume of earth; however, in general the forward end of the bowl is substantially open except as partially closed by the rotary loading structure 94, as also shown in FIGURE 7.

The rotary loading structure includes a pair of blades or scoops 96 and 98 (FIGURE 7) which are somewhat arcuate or concave-convex in section and elongate to extend substantially across the width of the open bowl 92. Specifically, the scoops 96 and 98 extend between a pair of large rotary gear wheels 100 (FIGURE 7) which are carried on an axle 102 that is supported by a pair of movable arms 104 that are pivotally mounted at a point 108 to swing relative the forward end 106 of the mobile frame 90 which is integral with the bowl 92.

The central axle 102 (FIGURE 11) of the loading structure 94 extends between bearings 107 in the pivotal arms 104 mounted outside, at the exterior of the bowl 92. Traversing inward from the bearings, the axle passes through the gear wheels 100 to emerge as an enlarged central section at shoulders 109, adjacent which, the axle is carried in a bearing structure 111 to enable the gear wheels 100- to freely turn thereon. The bearing structure 111 incorporates both roller bearings and thrust bearings.

As indicated, scoops 96 and 98 transverse a circular pattern about the axle 102 while remaining vertical, somewhat in planetary fashion on the gear wheels 1100, to effectively load the bowl 92. The scoops 96 and 98 are carried on integrally-formed axles 113 and 115 the ends of which are journalled into bearings in the gear wheels 110 at diametrically opposed locations so these axles remain parallel as the gear wheels 100 revolve.

The rotation of the large gear wheels 100 to drive the scoops 96 and 98 is accomplished by a chain drive with power take-ofi from the rear engine 14. Specifically, as shown in FIGURE 6, the rotary output of the transmission 88 is applied through a bevel-gear drive 103 to drive a transverse shaft 114 (see also FIGURE 10) as considered below which carries sprockets 116 (FIGURE 10) which drive endless lengths of chains 118 to revolve sprocket gear wheels 120 (FIGURE 6) which in turn are coupled by a short chain drive 122 to squirrel cage gear wheels 126 (FIGURE 6a). The squirrel cage gear wheels 126 (FIGURE 6a) comprise concentric opposed discs 128 and 130 held spaced apart on an axle 132 (extending across the unit) by rod-like gear teeth 134. These gear teeth matingly engage the large teeth 136 of the gear wheels 100 whereby to revolve the gear wheels 100 moving the loading blades or scoops 96 and 98 through a circular pattern. It is to be noted, that in this loading operation, the teeth of the large gear wheels 100 are exposed to direct contact with loose earth. That is, as shown in FIGURE 6a, it is readily apparent that loose earth is directly contacted by the individual teeth 136 on the gear wheels 100. As a result, a rather peculiar arrangement is embodied in the squirrel cage gear wheels 126 and the detailed structure of the gear wheels 100. Specifically, the teeth 136 on the large gear wheels 100 are separated by open spaces bottomed by an outwardlyextending apex form 138. That is, the space between each of the teeth 136 in the large gear wheels 100 is occupied by a somewhat triangular uniform section so that as the tubular gear teeth 134 of the squirrel cage gear wheels fall into these spaces, earth which might otherwise be packed therein is forced out the sides of the gear wheels, along the surfaces of the triangular form 138. As a result, earth cannot pack in the recesses of the large gear wheels 100 to lock those gears or block further movement.

In driving the large gear wheels 100 to turn the blades or scoops 96 and 98, the loop chains 118 are contained in diagonally-extending channels 139 (FIGURE 7) which are integrally defined in the sides of the bowl 92. These channels extend from a location of some middle height on the bowl 92 at the rear thereof to the sprockets 120 above the bowl at the forward end thereof. It is to be noted that the axes of sprockets 120 are also the centers of rotation for the pivotally movable arms 104. Above these arms, the bowl side walls rise to form forward extensions 141 for connection to activators.

The chain drives 122 are housed adjacent the forward extensions 141 (FIGURE 6) sealed within the wall of the bowl 92. These drives each include a sprocket 120, carried atthe ends of an axle 143 (FIGURE 11) extending across the bowl 92. Idler gears 145 (FIGURE 6) hold the chains 118 engaged with the sprockets 120 and outboard extensions of the axle 143 carry small sprockets 147 which mesh with chains 149, received on sprockets 151 carried at the ends of the axle 132 which also carries the squirrel cage gear wheels 126. Thus, the chain drives act to drive the gear wheels 126 and apply peripheral drive to the large gear wheels 100.

As the large gear wheels 100 are revolved by the squirrels cage gear wheels 126, the scoops 96 and 98 are held vertical by chain and sprocket drives contained within the gear wheels 100. As indicated above, during their movement through a rotary path, the blades or scoops 96 and 98 are held somewhat vertical by chain drives 140 whereby the concave faces of the scoops continually face the interior of the bowl 92. An endless loop of chain 142 (FIGURE 6) in each gear wheel 100 passes over drive sprockets 144 and 146 axially affixed to the scoops 96 and 98. The chain 142 is held against a central sprocket 150 by idlers 152 and 154. The central sprocket 150 is coaxial with the large gear wheel 100 and held stationary so that the planetary revolving drive sprockets 144 and 146 are referenced to the central sprocket 150 by the chain 142 and thus hold the blades 96 and 98 substantially upright. That is, as the wheels 100 revolve, carrying the scoops 96 and 98 through a circular-pattern or orbit, on axles 113 and 115 journalled into bearings 153 the scoops are revolved by the loop of chain 142 relative the large gear wheels 100 so that the net effect is that the scoops are held vertically upright throughout their circular motion. This upright position of the blades 96 and 98 is important to the loading operation of accepting earth and transporting it into the bowl 92.

The earth cut loose for movement by the loading structure is excavated by the cutting blade 156 (FIGURE 7) which trails the leading edges of the structure which incorporate adjustably mounted bits 158. More specifically, the bits 158 comprise elongate sections of steel plate for example that are slidably mounted in elongate mating chambers 160 to lie somewhat angularly positioned between the vertical and horizontal to extend forward and downward from the bowl 92. The upper part of the bits 158 includes an integrally-formed threaded section 162 carrying adjustment nuts 164 which are received on either side of a collar 159 fixed in an upright bracket 161. Thus, the extension of the lower ends of the bits 158 from the chambers 160 may be adjusted in accordance with a particular cut or to compensate wear. Of course, a substantial load is carried by the bits 158 in trenching a space to receive the sides of the bowl 92 and preparatory to the cutting operation of the blade 156, at the forward edge of the bottom of the bowl 92. As indicated above, earth excavated by the pivotally mounted cutter blade 156 is accumulated so that it may be pushed rearward of the cutter into the bowl. In this regard, it is to be noted, that the distance between the lowest point of travel of the scoops 96 and 98 during their circular movement and the blade 156 (during use) is somewhat critical. In the embodiment as described in detail, it has been found desirable to provide this distance at some fifteen inches; however, in general, it has been determined that the clearance between the blade scoops 96 and 98 in the rotary pattern and the cutting edge of the blade 156 (when operative) as shown by the vertical distance d in FIGURE 6 should be at least ten inches. Somewhat related to this consideration, it is to be noted that the cutting blade 156 and the rotary structure carrying the scoops 96 and 98 may be variously positioned. Of course, the cutting blade 156 is variously positioned about a pivot shaft 163 depending upon the cut to be accomplished. The loading structure, including the scoops 96 and 98 is variously positioned by pivotal movement of the arms 104, depending upon whether the system is loading or unloading.

The movement of the cutting blade 156 (FIGURE 6) is accomplished by a linkage rod 164 extending rearwardly from the blade to a bellcrank 166 which is in turn coupled to a hydraulic actuator 168. The actuator 168 has two extreme positions which either set the bell crank 166 as shown, or alternatively forces the bell crank 166 in a counterclockwise direction to lift the blade 156 from a cutting position to a load-retaining position.

In carrying a load, with the cutter 156 in a raised position, conventional practice will also be to locate the scoops 96 and 98 in the positions shown so that the forward end of the bowl 92 is substantially closed.

When it is desired to discharge the earth load from the bowl 92, the front end thereof is opened by lowering the cutting blade 156 and swinging the scoops 96 and 98 forward. The cutting blade 156 is positioned by the actuator 168 while the scoops 96 and 98 are moved by horizontally mounted hydraulic actuators 171. The cylinders of these actuators are affixed to the sides of the bowl 92 and their plunger rods are coupled to the lower ends of the pivotally-mounted arms 104. Thus, upon expansion or the actuators 17-1, the arms 104- are moved to pivot forwardly lifting the large gear wheels 100, and the entire structure carried on the axle 102, to open forward end of the bowl 92.

The structure for discharging earth from the bowl 92 includes a push plate or ram scoop 170 (FIGURE 6) which operates in cooperation with a floor structure 172 to unload the bowl 92 at a controlled rate. The ram scoop 178 extends substantially the entire rear end of the bowl 92 and is integrally formed with a pair of horizontally extending drive racks 174. The scoop 170, when withdrawn, abuts a stop 177 at the rear of the bowl 92. In such a position, a detent 179 formed in the scoop matingly receives a segment of the control structure as described below. As the scoop 170 is driven forward, four rollers 181 afiixed at the sides therof engage the sides of the bowl 92 and avoid any binding.

The drive racks 174 for the scoop 170 are also supported on rollers, specifically the rollers 183. These racks v1'74 incorporate gear teeth 176 which are fixed to extend transversely across the width of each rack 174. These teeth 176 engage gear wheels 178 which are driven by the engine 14 through the transmission 88 to move the scoop 170 forward forcing the loose earth from the front end of the bowl 92.

It is evident that in view of the large capacity of the bowl 92, a tremendous force would normally be required to drive the scoop 170 to slidably displace all the earth contained within the bowl 92. However, in accordance With the present invention, a peculiar structure is cmbodied in the floor of the bowl to avoid such necessity, and will now be considered in detail. The lower floor or the bowl 92 comprises a reinforced double-thickness section 180 which is rigidly affixed as the bottom of the bowl. A second or upper floor 182 is then carried on roller bearings to move with relatively little friction from the rear of the bowl 92 as shown in FIGURE 7 to a forward position in the bowl 92 adjacent the cutter blade 156. More specifically, the floor 182 defines a pair of spaceapart parallel risers 184 (FIGURE 10) in which rollerbearing containing chambers 186 (FIGURE 6) are provided. Thus, four somewhat fiat endless chambers 186 are provided to carry the rollers 188 which permit the upper floor 182 to be displaced over the bottom or lower floor 180 in low-friction roller relationship.

To avoid any binding of the movable upper floor 182 against the sides of the bowl 92, vertical rollers 190 (FIGURE 10) are afiixed at the corners of the upper floor 182. As a result of this structure, when the pusher scoop 170 (FIGURE 6) is driven forward to engage a load of earth carried in the bowl 92, it causes the floor 182 to move forward carrying the subtended load with very little friction so that virtually all the force of the scoop 170 is applied to slidably dispose that portion or" the load which rests above the forward section 180 of the floor. Of course, after substantially one-half the load has been discharged by the controlled forward motion of the pusher scoop 170, the tapered leading edge 189 of the upper section of floor 182 engages a stop 191 to limit further forward travel, with the result that the pusher scoop 170 then moves relative the floor 182 to slidably dispense the remaining earth carried thereon. Of course, at this stage of unloading the force required to slidably displace the remaining load has diminished substantially, with the result that sufiicient force is readily available. It is to be noted, that although only a single section of slidable floor is provided herein, various numbers of sections of displaceable floor can be readily employed and adapted for use in dilferent systems in accordance herewith.

In view of the above preliminary description of the system hereof, further understanding of the structure and its various modes of operation may now be best understood by assuming sequences of operation and actuation of various apparatus which will be described in detail along with the introduction of various other component parts within the apparatus as they are involved. Thereafter, the manner of controlling the various operating apparatus will be considered.

In operation of the unit as disclosed herein, the tractor 2 carrying the engine 6 and a hydraulic pump 56 as well known in the prior art will normally propel the unit to an excavating location. In this regard, the tractor 2 incorporates steering and control mechanisms as generally well known in the prior art and which therefore need not be described in detail herein. At the excavation location, the rear engine 14 of the unit is also started, drawing fuel from a tank 194 (FIGURE 6) and actuating the transmission 88 to provide additional propulsion for driving the cutter blade 156 and to power the loading and unloading structures.

Preliminary to performing an actual cutting operation, the side bits 158 (FIGURE 6) may be adjusted to compensate for any prior wear and also to provide the desired lengths of extension in accordance with the type of earth to be excavated. Next, the actuator 168 (FIGURE 6) is operated to revolve the bell crank 166 in a clockwise direction thereby setting the cutting blade 156 in a desired operative position somewhat as shown. As stressed herein, the critical distance from the leading edge of the cutting blade 156 and the nearest point of travel by the blades 96 and 98 is in excess of ten inches.

Continuing with the sequence of operation, the next step may be to preliminarily set the cutting level of the cutting blade 56 by establishing the angle of attack of the mobile frame. This angle is established by a pair of vertically offset hydraulic actuators 198 (FIGURE 7). The actuators 198 are pivotally connected at both ends between the yoke arms 200 coupled to the tractor 2 (FIGURE 7) and the forward extensions 141 from the bowl 92. The yoke arms 200 are attached respectively by a pair of pivot mountings 202 at the forward lower portion of the bowl 92. On application of hydraulic drive fluid to the actuators to increase their length, the forward portion of the bowl 92 is raised to vary the angle-ofattack.

After establishing a preliminary angle-of-attack, and cutting blade setting, the unit will normally be driven, with power applied to both sets of wheels 8 and 10 from the independent engines. In the normal course of use, the cutter blade 156 (FIGURE 6) encounters the earth to be graded and cuts the earth loose in an excavating manner. It is to be noted, that this cutting operation is accomplished by the force applied to propel the entire structure forwardly and is therefore exceedingly effective. As earth is cut loose and accumulated behind the cutting blade 156, the loading structure 94 distributes the earth within the bowl 92.

As the large gear wheels 100 of the loading structure 94, revolve the scoops 96 and 98 travelling in a rotary pattern shift earth from the accumulation developed by the cutter blade 156 thereby raising the earth for distribution within the bowl 92. In actual operation, it occurs that the cooperative relationship of the loading scoops 96 and 98 with the cutting blade 156 accom plishes a substantially uniform load within the bowl 92, even though the capacity of the bowl 92 i well in excess of fifty cubic yards.

As the cutting and loading operation progresses, the angle-of-attack and the position of the cutter blade 156 may be varied by operating the actuators 168 and 198 FIGURE 7). Of course, such adjustment will depend upon the desired cut and the type of earth under excavation. However, the loading structure 94 will normally be allowed to run continuously, requiring none of the operators attention.

Upon completing a load in the bowl 92, the loading structure including the blades 96 and 98 is stopped at a position with the blades substantially vertical as shown in FIGURE 7. To further close the open end of the bowl 92, the actuator 168 is motivated to revolve the bell cr-ank 166 in a counterclockwise direction whereby lifting the cutting blade 156 to retain earth within the bowl 92. By these closures, the earth in the bowl 92 is substantially contained for transportation to a desired location. At this time the hydraulic actuators 198 will normally be extended to raise the forward end of the bowl 92 for travel.

On unloading the bowl 92, the rate of discharge may be controlled to spread the earth over a substantial area. Preparatory to unloading or off-loading the earth, the cutter blade 156 (FIGURE 6) is partly lowered and the blades 92 and 98 are lifted by the hydraulic actuators 171. It is to be noted, that during this phase of operation, the actuators 198 (FIGURE 7) hold the forward end of the bowl 92 somewhat elevated providing a space between the blade 156 and the grade line.

To actually discharge earth from the bowl 92, the gear wheels 178 (FIGURE 6) are driven, moving the racks 176 to drive the unloading scoop forward and applying a shifting force to the entire contents of the bowl 92. As previously described, the rear portion of the load slides forward readily on rollers 188 while the forward portion of the load slides forward overcoming frictional forces and is dispensed from the open forward end of the bowl 92. When substantially one half the load is discharged the travelling floor 182 engages a stop 191 and the unloading scoop 170 continues its travel to slidably pass over the now-displaced floor 182 discharging the remainder of the load.

After the load has been discharged, the scoop 170 is discharged so that it may be returned to the position as shown in FIGURE 6 by -a fresh load as it is accumulated in the bowl 92. Alternatively this return is accomplished by the gear wheel 178 (FIGURE 6) which is driven in clockwise direction as described below to return the scoop.

Considering the actuation of the various apparatus, driving power is provided from the transmission 88 (FIG- URE 12) to a rotary shaft 216 which is connected by a coupling 218 to a rotatably mounted shaft 220 entering the clutch control unit 221. The shaft 220 is supported in bearings 222 and carries a bevel gear 224 which in turn engages a mating gear wheel 226 rigidly affixed to a rotary hollow shaft 228 that telescopically receives a supporting solid shaft 230 the ends of which are journalled into rotary coupling shafts 232 and 234 (also shown in FIGURE 9) which extend to gears 236 for driving the chain which actuates the loading structure 94.

Mounted on either side of the central gear wheel 226 (FIGURE 12) are clutches 240 and 242 for selectively engaging the gear wheel 226 to either the loading apparatus or the unloading apparatus. Specifically, the clutch 242 engages the gear Wheel 226 to the coupling shafts 232 and 234 for the loading structure while the clutch 240 engages the gear Wheel 226 to a sprocket 224 which is in turn meshed with a chain drive and gear train 246 (FIGURE 9) that terminates in the gear wheel 247 for driving a shaft 249 which in turn carries the gear wheels 1 1 178, the teeth of which mesh with the tubular gear teeth 176 in the rack 174 which serves to displace the unloading scoop 170.

The chain drive and gear train 246 originates at the sprocket 244 (FIGURE 12) which drives a chain 251 (FIGURE to in turn drive the shaft 249 through a series of reduction gears 253. The shaft 249 is supported by brackets 255 (FIGURE 9) which extend at the sides of the control unit 221 as supported on a frame 257.

Considering the details of the clutches 240 and 242 within the control unit 221 (FIGURE 12) these components are somewhat similar and are essentially hydraulic control clutches which engage a pair of mating elements when subjected to pressure and otherwise provide no engagement. Of course, other well-known forms of hydraulic clutches could be readily substituted.

In the clutch 240, a fluid-containing housing 250 defines a somewhat cylindrical internal chamber concentrically containing a flexible external clutch member 252 incorporating a bellows series of rotary clutch plates 254 which are interleaved with open clutch plates 256. The plates 254 are aflixed to the clutch member 252 which is in turn connected by a collar 258 to the external rotary shaft 228 carried in bearings 257. The collar 258 incorporates ball bearings 261 spacing the shaft from a rotary structure 260 (carrying the sprocket 244) concentrically received on the shaft 230 and fixed in bearings 259. The clutch plates 256 are also integral with the rotary structure 260 so that upon the application of pressure into the chamber 265, flexible plates 254 are resiliently distorted to engage the clutch plates 256 thereby coupling the external rotary shaft 228 to the rotary structure 260. Hydraulic pressure for such control is provided through a duct 262 which is connected through a valve 264 to a relief line 266 and to a pressure line 268.

In a somewhat similar manner, the hydraulic bellows clutch 242 functions to couple the gear wheel 226 to the internal rotary shaft 230. Specifically, the gear wheel 226 is coupled by the shaft 228 to an external bellows structure 270 incorporating clutch plates 272 for engagement with mating clutch plates 274 upon pressurization of the chamber 267 in the clutch 242 through a hydraulic line 276. The internal plates 274 are joined at a hub 278 which is locked by a key 280 to the central shaft 230. Pressurization of the chamber 267 as well as relief thereof is accomplished through a valve 282 which is in turn connected to a pressure line 284 and a relief line 286. Thus, upon the application of pressure to the clutch 242, engagement is accomplished between the gear wheel 226 and the central shaft 230 which is in turn coupled through coupling shafts 232 and 234 (FIGURE 10) to sprockets 116 for driving the chains 118 and thereby motivating the rotary structure and specifically the large gear wheels 100. Also shown in FIGURE 12 is represented section is a hydraulic motor 290 which may be used to withdraw the pusher scoop 170. The motor may take any of a variety of structural forms well known in the prior art and is therefore not shown in detail. The motor is mechanically coupled to the gear wheel 244 and drives that gear in a direction opposed to the drive through the clutch 240', so as to withdraw the pusher scoop 170. The motor 290 is controlled by a valve 292 through which it is connected to a source of hydraulic fluid under pressure.

In general, the entire structure will normally be manufactured of steel, incorporating reinforcement where necessary to support various loads. For example, the bowl 92 may be formed of steel plates ribbed by reinforcement channels 273 (FIGURE 7) extending 'both horizontally and vertically as indicated in FIGURE 6. The mobile frame 106 of the structure will normally be a somewhat open beam construction depending upon specific design considerations. The engines 6 and 14 of the structure may also vary widely; however, in the embodiment as described, large diesel engines are provided. Such structures as power transmissions, couplings, actuators, power trains, and the like may take any of a wide variety of different forms as well known in the prior art; however, as described herein the illustrative embodiment employs considerable hydraulic structure in this regard.

It may therefore be seen, that apparatus incorporating the principles of the present invention are capable of selfloading operation to provide a high capacity load operation to effectively transport such a load; and to discharge such a load at a controlled rate. These features result from the cooperative relationship of the independent elements of the system. Of course, the novel relationship of these elements may be incorporated in various structures to accomplish. the attendant advantages of the present invention and therefore the scope hereof shall be interpreted in accordance with the appended claims.

What is claimed is:

1. An earth carrier comprising:

a mobile frame;

a bowl afiixed on said frame and including a rear end wall, a pair of side walls, and an elongate, substantially-flat bottom, the forward edges of said side walls and said bottom defining a forward opening;

means for loading said bowl with earth;

a movable floor section extending over a portion of said elongate bottom;

roller means carried by said movable floor section and thereby constrained between said elongate substantially flat bottom and said movable floor section for accommodating free motion of said floor section over said elongate bottom;

means for limiting the movement of said floor section whereby not to extend beyond the edges of said bottom; and

a push-out ejector for traversing from a rearward location over each of said floor sections and said bottom to extend substantially through said bowl whereby to discharge earth therefrom by initially displacing said movable floor section forwardly and subsequently traversing over said floor section to remove earth therefrom.

2. An earth carrier according to claim 1 wherein said means for loading said bowl includes a cutter blade affixed to said bottom, contiguous said forward opening,

for scooping earth into .said bowl and a rotary structure aflixed to said carrier contiguous to said forward opening, for moving earth rearward and upward from said cutter blades.

3. An earth carrier according to claim 2 wherein said rotary structure comprises a plurality of elongate blades having substantially-parallel horizontal central axes and aflixed into said rotary structure whereby to be moved in a rotary pattern preserving said axes parallel and said blades upright therethroughout.

4. An earth carrier according to claim 1 further comprising bearing means supported between said movable floor section and said bottom whereby to accommodate relative movement therebetween.

5. An earth carrier according to claim 1 wherein said push-out ejector comprises a scoop and means for moving said scoop across said movable floor section to remove earth therefrom.

6. An earth carrier according to claim 1, further including a plurality of roller-bearing circuit chambers and a plurality of roller bearings contained in each of said chambers said circuit chambers being aflixed to position said rollers to afford roller engagement between said bottom and said movable floor section.

7. An earth carrier according to claim 6 further including a plurality of vertical rollers supportedly aflixed perpendicular to said roller bearings and mounted to provide roller engagement between said bowl and said movable floor section.

8. An earth carrier according to claim 6 wherein said 2,422,813 6/1947 Walch.

push-out ejector comprises a scoop and means for moving 2,475,301 7/ 1949 Zakel. said scoop across said movable floor section to remove 2,844,892 7/1958 Carston 374 earth therefrom. 3,274,711 9/1966 Johnson et a1 37-129 References Cited 5 ROBERT E. PULFREY, Primary Examiner UNITED STATES PATENTS E. H. EICHHOLT, Assistant Examiner 2,112,105 3/1938 Tourneau. s L

2,229,103 1/1941 Tourneau. 37-429; 21482 

